7-(4-Meth­oxy­phen­yl)-4,9-dimethyl-N-(4-methyl­phen­yl)-5,12-diaza­tetra­phen-6-amine

K N Vennila; K Prabha; K J Rajendra Prasad; D Velmurugan

doi:10.1107/S1600536811006209

. 2011 Mar 2;67(Pt 4):o762–o763. doi: 10.1107/S1600536811006209

7-(4-Methoxyphenyl)-4,9-dimethyl-N-(4-methylphenyl)-5,12-diazatetraphen-6-amine

K N Vennila ^a, K Prabha ^b, K J Rajendra Prasad ^b, D Velmurugan ^a,^*

PMCID: PMC3099846 PMID: 21754058

Abstract

In the title compound, C₃₂H₂₇N₃O, the fused tetracycilc ring system is essentially planar [r.m.s. deviation = 0.07 (7) Å]. An intramolecular N—H⋯π(arene) interaction and a weak intramolecular C—H⋯N hydrogen bond may influence the molecular conformation. In the crystal, weak intermolecular C—H⋯N hydrogen bonds link the molecules into centrosymmetric dimers, forming R ₂ ²(14) motifs. In addition, weak π–π stacking interactions with centroid–centroid distances in the range 3.578 (1)–3.739 (1) Å provide further stabilization.

Related literature

For the biological activity of naphthyridine derivatives, see: Gopalsamy et al. (2007 ▶); Kim et al. (2009 ▶); Nittoli et al. (2010 ▶); Bedard et al. (2000 ▶). For the structures of related naphthrydine derivatives, see: Peng et al. (2009 ▶); Seebacher et al . (2010) ▶; Vennila et al. (2010a ▶,b ▶). For standard bond lengths, see: Allen et al. (1987 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶).

Experimental

Crystal data

C₃₂H₂₇N₃O
M _r = 469.57
Monoclinic,
a = 8.3816 (6) Å
b = 23.1651 (13) Å
c = 12.8548 (7) Å
β = 91.171 (3)°
V = 2495.4 (3) Å³
Z = 4
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 293 K
0.29 × 0.24 × 0.23 mm

Data collection

Bruker SMART APEXII area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2004) T _min = 0.978, T _max = 0.983
24206 measured reflections
6239 independent reflections
3904 reflections with I > 2σ(I)
R _int = 0.029

Refinement

R[F ² > 2σ(F ²)] = 0.053
wR(F ²) = 0.181
S = 0.95
6239 reflections
329 parameters
H-atom parameters constrained
Δρ_max = 0.27 e Å⁻³
Δρ_min = −0.23 e Å⁻³

Data collection: APEX2 (Bruker, 2007 ▶); cell refinement: SAINT (Bruker, 2007 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: ORTEP-3 (Farrugia, 1997 ▶); software used to prepare material for publication: SHELXL97 and PLATON (Spek, 2009 ▶).

Supplementary Material

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536811006209/lh5193sup1.cif

e-67-0o762-sup1.cif^{(25.2KB, cif)}

Structure factors: contains datablocks I. DOI: 10.1107/S1600536811006209/lh5193Isup2.hkl

e-67-0o762-Isup2.hkl^{(305.4KB, hkl)}

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

Table 1. Hydrogen-bond geometry (Å, °).

Cg is the centroid of the C17–C22 ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N3—H3⋯Cg	0.86	2.48	3.336 (3)	176
C28—H28⋯N1	0.93	2.37	2.927 (3)	118
C18—H18⋯N2ⁱ	0.93	2.55	3.435 (2)	159

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Symmetry code: (i) Inline graphic .

Acknowledgments

KNV thanks the CSIR, New Delhi, for financial assistance in the form of a Senior Research Fellowship. DV acknowledges the Department of Science and Technology (DST) for providing data-collection facilities under the TBI program and also thanks the DST for financial support under the UGC–SAP and DST–FIST programs.

supplementary crystallographic information

Comment

Dibenzo-naphthyridine analogs have been reported to be good Phosphoinositide-Dependent Kinase (PDK-1) inhibitors. Gopalsamy et al. (2007) and Kim et al. (2009) have described the synthesis and structure activity relationship analysis of a novel series of benzo[c][2,7]naphthyridines as potent PDK-1 inhibitors. Recently a few X-ray crystal structures of PDK-1 and dibenzo[2,7] naphthyridine analog complexes have been reported (Gopalsamy et al., 2007; Nittoli et al., 2010). A series of dibenzo-naphthyridines were sucessfully tested for anticancer assays (Gopalsamy et al., 2007; Nittoli et al., 2010). The naphthyridine compounds were also proven to exhibit potent activity against human cytomegalovirus (Bedard et al. , 2000). As we are focussing on heterocyclic naphthyridine derivatives with potential biological properties, the crystal structure of the title compound was determined.

The molecular structure of the title compound is shown in Fig. 1. The bond lengths and angles are in the normal ranges (Allen et al., 1987). The fused tetracyclic ring system is essentially planar in geometry as was previously reported for a related compounds (Vennila et al., 2010, 2011; Seebacher et al. 2010; Peng et al. 2009). An intramolecular N—H···π(arene) interaction and a weak intramolecular C—H···N hydrogen bond may influence the molecular conformation. In the crystal, weak intermolecular C—H···N hydrogen bonds link the molecules into centrosymmetric dimers forming R₂²(14) motifs (Bernstein et al., 1995) (see Fig. 2). In addition, weak π–π stacking interactions with centroid to centroid distances in the range 3.578 (1) - 3.739 (1) Å provide additional stabilization.

Experimental

A mixture of 4',4''-dimethyl-2,4-bis-(N-phenylamino) quinoline (0.0010 mol) and p-methoxybenzoic acid (0.0011 mol) was added to polyphosphoric acid (3 g of P₂O₅ in 1.5 mL of H₃PO₄) and kept at 323-328K for 5 h. The reaction was monitored by TLC. After the completion of the reaction, the reaction mixture was poured into ice water and neutralised with saturated NaHCO₃ solution to remove the excess of p-methoxy benzoic acid. The precipitate was filtered, dried and purified by column chromatography over silica gel using petroleum ether : ethyl acetate (98 : 2). The product was recrystallised using ethyl acetate.